Can I save regular expressions I use all the time? In particular, I search on C-style identifiers a lot.
If you bring up any of the search dialogs you’ll notice a button labeled Alias. This brings up a list of pre-defined regular expressions. The one you’re after is <vc>, which is defined (as you can easily see by clicking on the Edit button with that item selected) as [A-Za-z_\$][A-Za-z0-9_\$]*. You needn’t open the Regular Expression Aliases dialog to use them, although that is one way, especially if you don’t remember what one is called. You can also add your own aliases via this dialog.
One very important caveat: do not modify any of the existing aliases, even by changing their names, as some of them are actually used by various of the Multi-Edit system macros. For instance, were you to change, say, <fc>, you’d find that a lot of important C functionality, such as Multi-tags, for instance, would cease to function.